A ribosome is a cellular organelle found in all living cells. It is responsible for synthesizing proteins, which are essential for the structure, function, and regulation of the body’s tissues and organs.Image by brgfx on Freepik
The big subunit and the small subunit are the ribosome’s constituent parts. Ribosomal RNA (rRNA), a kind of RNA essential for protein synthesis, is found in the large subunit. It is the tiny subunit that binds to messenger RNA (mRNA), which holds the genetic instructions for the protein being produced.
During protein synthesis, the ribosome reads the genetic code on the mRNA molecule and translates it into a specific sequence of amino acids. It does this by binding to transfer RNA (tRNA) molecules, which carry specific amino acids to the ribosome. The ribosome then joins the amino acids together in the correct order to form a protein chain.
Ribosomes are found in both prokaryotic and eukaryotic cells, but they have slightly different structures and functions in each type of cell. In prokaryotes, ribosomes are found throughout the cytoplasm, while in eukaryotes, ribosomes are found in the cytoplasm and also in the endoplasmic reticulum, where they are involved in the synthesis of proteins that will be secreted from the cell or incorporated into the cell membrane.
Functions of ribosome
The main function of ribosomes is to synthesize proteins, which are essential for the structure, function, and regulation of the body’s tissues and organs. Protein synthesis occurs through a process called translation, in which the ribosome reads the genetic code on mRNA molecules and translates it into a specific sequence of amino acids.
Here are some answers to common questions about ribosomes:
What is the structure of a ribosome?
A ribosome is made up of two subunits, called the large subunit and the small subunit. The large subunit contains ribosomal RNA (rRNA), which is a type of RNA that plays a central role in protein synthesis. The small subunit contains proteins and also binds to mRNA, which carries the genetic code for the protein being synthesized.
Where are ribosomes found in the cell?
Both prokaryotic and eukaryotic cells have ribosomes. Ribosomes in prokaryotes are distributed throughout the cytoplasm, while in eukaryotes they are located in the cytoplasm and the endoplasmic reticulum, where they are involved in the production of proteins that will be secreted or integrated into the cell membrane.
How do ribosomes play a role in the production of proteins?
Protein synthesis involves ribosomes reading the genetic code from mRNA molecules and then translating that into an ordered chain of amino acids. This is achieved by attaching to transfer RNA (tRNA) molecules, which are responsible for transporting individual amino acids to the ribosome. After that, the ribosome puts the amino acids in the right order to make a protein chain.
How are ribosomes involved in the regulation of gene expression?
Protein synthesis can be controlled at either the transcriptional (where the mRNA is made) or translational (where the mRNA is read and translated into a protein) levels. This enables cells to regulate protein abundance in response to external cues.
What role do ribosomes play in the modification and folding of proteins?
Chemical groups are frequently added to the protein chain or amino acids are removed when it is being produced. The freshly manufactured protein may then require a specific three-dimensional shape for proper function, and the ribosome may collaborate with other proteins in the cell to achieve this.